KR20000052409A - Recording device, interface card for using the same, and method for sending recording data from a host computer to the recording device - Google Patents

Abstract

PURPOSE: An interface card for connecting a recording device to a host computer is provided to reduce time required for data decompression or compression by easily exchanging a decompression or compression function supplied to a recording unit with the host computer having a function of decompression/compression. CONSTITUTION: An interface card detachably mounted in a recording device, e.g. a printer, has a first interface(18) connected to a host computer(20), a second interface(19) connected to a control board(11) of the recording device(10), first decompression means(30) for decompressing data received from the host computer(20), memory means(31), and control means(17). The control means is adapted to determine whether the control board(11) is equipped with second decompression means(40) and, if so, to compare control data indicating the performance of said first decompression means(30) with control data indicating the performance of said second decompression means(40). Depending on the comparison result that one of the two decompression means that performs better than the other one is enabled to decompress data received from the host computer, while the other decompression means is disabled.

Description

Recording device, interface card for using the same, and a method for sending recording data from the host computer to the recording device. {Recording device, interface card for using the same, and method for sending recording data from a host computer to the recording device}

The present invention relates to a recording device such as a printer connected to a host computer operating in response to a command from a host computer and a method for transferring recording data from the host computer to the recording device. In particular, an interface detachably installed in the recording device. It's about the card.

The amount of data exchanged between the host computer and the recording device is steadily increasing. This is also because the data density of recording or printing is high, and the recording or printing mode has been variously increased. However, there is still a strong demand for higher speeds in the recording or printing process, and there is also a need for techniques that support high speed data transfer.

The higher data processing speeds of host computers and recording devices have increased the amount of data transferred per unit time. However, as long as the current interface normally used for recording devices (such as RS232C or Centronics) is used, the transfer rate is limited.

Under these circumstances, an effective way to reduce the amount of data to be transmitted is to compress the data with a predetermined algorithm at the transmitter (e.g., the host computer) and restore the data to its original form at the receiver (e.g., the recording device). It is to recover.

Incidentally, a printer is known which has an interface card detachably installed in the printer. Various interface cards correspond to various interfaces between various host computers and recording devices, such as RS232C, Centronics or Universal Serial Bus (USB). Thus, by replacing such an interface card, various interface compatibility is possible.

For example, JP-A-8-164640 discloses a printer system in which a host computer is connected to a printer via a network board connected to a printer via a network. In such a printer system, the network board has a data restoration control area for restoring compressed printing data transmitted from a host computer.

However, when communicating between a recording device and a host computer using such compressed data, the receiver is required to recover the data with the same algorithm used at the transmitter to compress it. Thus, the data compression / restore function provided to the host computer needs to be the same as that provided to the recording device.

Therefore, the compression / restoration function of the recording apparatus must be compatible with the compression / restoration function of the specific host computer used with this recording apparatus.

If either the host computer, the interface card or the recording device is replaced while in use, or the compression / restore algorithm is replaced with another algorithm, the exchange of compressed data between the host computer and the recording device becomes impossible, or the transfer rate or throughput May cause the problem to slow down.

In addition, if each of the recording device and the interface card has its own compression / restore function to reduce the time required for data processing, any of the compression / restore functions may be the best function for exchanging compressed data with a host computer. You have to decide

Therefore, it is an object of the present invention to overcome the above mentioned problems.

It is an object of the present invention to provide a solution to this problem by making the compression / restoration function provided in the recording apparatus easily replaceable, making it compatible with the compression / restoration function provided in the host computer. Another goal is to provide compatibility with host computers with various compression / restore functions.

1 is a block diagram showing a recording apparatus of a first embodiment of the present invention;

2 is a flow chart illustrating a procedure for performing printing by transferring data from a host computer to a recording device.

3 is a block diagram showing a recording apparatus of a second embodiment of the present invention;

4 is a flow chart showing the steps up to comparing compression / restore performance, illustrating a procedure for performing printing by transferring data from a host computer to a recording device.

Fig. 5 is a flowchart showing the steps of restoring the compressed data in the interface card, and showing a procedure for executing printing by transferring data from the host computer to the recording device.

Fig. 6 is a flowchart showing the steps of restoring the compressed data in the control board of the recording apparatus, and showing a procedure for executing printing by transferring data from the host computer to the recording apparatus.

In order to achieve the above object, an interface for communication with a host computer should be formed as a card (interface card) in the recording apparatus of the present invention so as to be replaced independently of the recording apparatus. In particular, the interface card must be detachably connected to the control board, which is provided in the recording apparatus and has a first controller for controlling the recording apparatus.

A first decompressor for recovering the compressed data received from the host computer is provided in the interface card. This makes it possible to select or replace the recovery function of the recording device so as to be compatible with the compression algorithm in the host computer without replacing the entire recording device.

A second controller is also provided on the interface card. This second controller allows the first decompressor to recover the compressed data by comparing the data processing performance to restore the compressed data between the control board and the interface card.

Furthermore, the present invention may include a control board provided with a second decompressor capable of restoring compressed data. The second controller allows either one of the first and second decompressors to recover the compressed data by first comparing the performance between the control board and the interface card.

This can reduce data processing time by recovering compressed data with a better decompressor for data decompression performance.

The present invention includes a first compressor provided on an interface card. The first compressor can compress the data for communication with the host computer.

The present invention also includes a second compressor installed in the recording apparatus and provided on the control board. The second compressor can compress the data for communication with the host computer. In such a configuration, the second controller compares data processing performance between the control board and the interface card, thereby allowing either the first or second compressor to compress the data.

This can reduce the data processing time required by compressing the data using a better compressor for data compression performance when the compressed data is sent to the host computer.

Moreover, in the present invention, a plurality of different algorithms, preferably for recovering or compressing data, are provided in each of the first decompressor and the first compressor.

The present invention also relates to a method of transferring recording data from a host computer to a recording device, which method works well under a recording system, wherein an interface card having one first restoring device is separated from a control board installed in the recording device. It is possibly connected, and the host computer communicates with the control board via the interface card.

The method includes the following steps:

(a) a determining step of determining an algorithm for compressing / restoring recording data available for at least one of the host computer and the interface card and the control board;

(b) enabling the first decompressor if the control board does not have a decompressor capable of restoring the compressed data according to the algorithm determined in step (a);

(c) when the control board has one second recoverer capable of restoring the compressed data, data processing capability of restoring the compressed data of the control board and data restoring the compressed data of the interface card; A comparison step of comparing the processing performance;

(d) enabling, according to the result of step (c), one of the first and second recoverers;

(e) a transmission step of compressing the recording data in the host computer according to the algorithm determined in step (a), and transmitting the compressed data to the interface card;

(f) a transmission step of recovering the compressed data in the interface card when the first recoverer is enabled, and transmitting the restored data to the control board;

(g) a restoration step of transmitting the compressed data to the control board and restoring the compressed data in the control board when the first restorer is disabled.

The present invention further includes a software program for executing the method of transmitting and receiving the record data of the present invention. The software program may be stand-alone, resident on a host computer, recorded on a medium or media readable by a host computer or recording device, or inserted into a carrier wave to be embedded in the host computer or recording device. Can be.

Other objects and attainments, together with a more general understanding of the invention, will be clearly understood by reference to the following description and claims, which are incorporated in the accompanying drawings.

Embodiments of the present invention will be described below with reference to the drawings. 1 is a block diagram of a recording apparatus of an embodiment of the present invention. 1 shows a host computer 20 connected to a recording apparatus 10. The recording apparatus 10 includes a printing mechanism portion 13, such as a sheet feeding mechanism and other mechanism portions, a control board 11A and an interface card 12 for overall control of the recording apparatus.

The interface card 12 is one board mounted in all circuits that execute functions related to communication between the recording device and the host computer, so as to form a single replaceable unit. Thus, by replacing the interface card 12, it can be compatible with various interfaces, such as RS232C, Centronics or Universal Serial Bus (USB), between various host computers and recording devices.

Except for the functions included in the interface card 12 and the printing mechanism portion 13, all the functions in the recording apparatus 10 are built in the control board 11A. That is, the control board 11A includes a controller 14 for controlling the printing mechanism unit 13; A ROM 15 storing program data and font data, a RAM temporarily storing printing data, and a memory 15 having control instructions and other information; And an interface card 16 for communicating with the interface card 12.

The replaceable interface card 12 is detachably connected to the control board. For example, the interface card may be inserted into or removed from the card slot of the main backplane, connected to the control board via a backplane connection, and if the backplane connection is not available, The control board can be connected by wire cable.

The interface card 12 includes a compressor / restorer 30, a controller 17 for controlling the card, an interface 18 for communication with the host computer 20, and an interface 19 for communication with the control board 11A. . The interface card 12 is provided with various communication interfaces corresponding to RS232C, Centronics or USB so as to use a communication interface compatible with the interface card used in the host computer 20.

The compressor / restor 30 installed in the interface card 12 provides the functions to compress / restore data and include printing data and control commands exchanged with the host computer 20. That is, the compressor / restorer 30 restores (recovers) the compressed data transmitted from the host computer to the original data, and transmits the data from the recording device 10 to the host computer 20 through the compression function. Compress the data.

The compressor / restore 30 is a standard data compression / restore algorithm such as run-length coding, Huffman coding, discrete cosine transform, Lempel-Ziv (LZ), JPEG, etc. Use As shown in FIG. 1, the compressor / restore 30 includes a plurality of different compression / restore algorithms, such that the interface card 12 compresses data that is compatible with the algorithm used by the host computer 20. And restore.

The compressor / restor 30 should be able to compress the data transmitted to the recording apparatus after being compressed by the compressor / restor 21 in the host computer 20. In addition, the compressor / restore 21 in the host computer 20 must restore the data transmitted to the host computer after it has been compressed by the compressor / restore 230. Since such compatibility is required, the compression / restore algorithm in the interface card 12 should be able to support one or more compression / restore algorithms of the compressor / restorer in the host computer 20.

The memory 31 of the interface card 12 provides the compression / restoration performance information. That is, in this embodiment, the memory 31 is supported by the type of printer (control board) to which the interface card can be connected, the type of compression / restore algorithm supported by each printer, and the interface card 12 itself. Stores a table containing information such as the type of compression / restore algorithm.

The controller 17 reads the information stored in the memory 31 to recognize the function of the control board 11A. In this embodiment, the algorithm used for exchanging data between the host computer 20 and the recording device is selected from the algorithms supported by both the interface card 12 and the host computer 20, because the control board ( This is because 11A) cannot support any compression / restore functions.

In the order of transferring the compressed data from the host computer 20 to the recording device 10, before generalizing the compressed data, the host computer 20 determines a compatible compression / restore algorithm that can be used for operation. And the interface card 12 of the recording apparatus 10 are exchanged. By using a compatible coding system for data compression, the recording device 10 can restore the compressed data.

Further, in the order of transferring the compressed data from the recording apparatus, the exchange is first executed to the host computer to ensure that the data is compressed by a coding system compatible with the decompression algorithm in the host computer 20.

The recording apparatus of another embodiment of the present invention will be described later. 3 is a block diagram of the recording apparatus of this embodiment of the present invention. In this embodiment, the same components as in the previous embodiment used the same reference numerals, and their description is the same as in the previous portion. This embodiment has the fact that the control board 11B includes a compressor / restorer 40 and memories 15 and 31 containing compression / restore performance information of each of the control board 11B and the interface card 12. Is different from the previous embodiment.

In this embodiment, the compressor / restorer 40 provided in the control board 11B supports one or more of the plurality of compression / restore algorithms included in the compressor / restorer 30 provided in the interface card 12. That is, the data compressed by any algorithms supported by both compressors / restors 30, 40 are recovered using either of the compressors / restors 30,40. In addition, data compression by this algorithm is possible by using any one of the compressors / restors 30 and 40.

The memory 15 and the memory 31 of the control board 11B and the interface card 12 respectively store compression / restoration performance information. Compression / restoration performance information is one or more types of numerical information indicating the compression and recovery data processing capabilities of each of the compressors / restors 30 and 40. That is, the information stored in the memory 15 is information about the data processing performance of the compressor / restor 40 installed in the control board 11B, and the information stored in the memory 31 is the compressor / installed in the interface card 12. Information regarding the data processing performance of the decompressor 30.

The performance information stored in the memories 31, 15 is, for example, for the type of algorithms supported by each of the compressors / restors 30, 40, the data compression ratio of each algorithm, for compression / restore per byte of each algorithm. Required data throughput, compression / restore block size, transfer rate between interface card 12 and control board 11B, throughput of each controller 17, 14, and the like.

If the compressor / restor 30,40 supports multiple compression / restore algorithms, each memory stores performance information for each algorithm.

In this embodiment, the program executed in the controller 17 of the interface card 12 performs a performance comparison function to compare the performance information stored in the memories 15 and 31, respectively.

The performance comparison function performed at the controller 17 is used to compress / restore data between the control board 11B and the interface card 12 as well as the execution of the two compressors / restors 30 and 40 themselves. For example, compare the overall performance to calculate the data rate.

That is, the controller 17 reads the compression / restoration performance information from each of the memories 15 and 31, compares them, and then enables one compressor / restorer with higher performance and disables the other.

For example, if, as a result of the comparison, the interface card 12 is determined to have higher data compression / restore performance than the control board 11B, the compressor / restore 30 in the interface card 12 may be replaced by the host computer. And compression to restore data exchanged between the recording device and the recording device. The compression performance is performed only during the first time data compression and decompression is required, i.e. only during the time when the interface card 12 is replaced.

Next, referring to the flow charts of FIGS. 2 and 4 to 6, the printing is executed in the recording apparatus 10 by transmitting printing data and control commands from the host computer 20 to the recording apparatus 10. Describe the procedure.

Initially, the controller 17 of the interface card 12 reads (step 200) the compression / restore performance information output from each of the memories 15 and 31.

Before sending printing data and control commands to the recording device 10, the controller 22 of the host computer 20 determines the interface card 12 of the recording device to determine whether the compression / restore algorithm is supported by the two devices. (Step 201). For example, in Figure 3 the RLE compression algorithm is determined.

The algorithm with the highest compression ratio is selected from the compressor / restor 21 and the compressor / restor supported by one or more of the compressors / restors 30,40.

In the interface card 12, the controller 17 determines (step 201B) whether the control board 11 (11B) supports the determined algorithm. If this is possible, as described in the embodiment of FIG. 1, the controller 17 enables (step 201C) the compressor / restore 930 to recover the compressed data transmitted from the host computer 20.

The data to be transmitted is compressed (step 202) by the compressor / restor 21 of the transmitting side (host computer 20) using a previously determined algorithm. Immediately after the data compression is completed, the controller 22 transmits the compressed data in the recording apparatus via the interface 24 (step 203).

In the recording device 10, the controller 17 of the interface card 12 generates a command (step 204) to the compressor / restore 30 for restoring the compressed data received via the interface 18. Send the command. In accordance with this command, the compressor / restorer 30 restores the compressed data according to the algorithm previously determined in the negotiation between the host computer and the interface card (step 203).

The recovered data is then sent (step 206) to the control board 11 via the interface 19. The controller 14 of this control board 11 interprets the control command contained in the restored data (step 207) and executes printing (step 208) according to the restored data.

Alternatively, if, in step 201B, the control board 11 (11B) supports the determined algorithm as shown in the embodiment described in FIG. 3, the control is controlled by the control board 11B and the interface card 12. The performance for restoring the data between the nodes is compared (step 403). This comparison involves reading information from the memory 15, 31 of the previous step 200.

As a result of this comparison, the controller 17 is enabled with any of the higher performance compressors / restors 30, 40, and the others are disabled (step 404). For example, compressor / restore 30 is enabled and compressor / restore 40 is disabled.

In the host computer 20, data compression is performed by a travel length coding (RLE) algorithm to transfer (step 406) the compressed data to the recording device 10 via the interface 24.

In the recording device 10, the controller 17 of the interface card 12 determines whether or not the function of its own compressor / restor 30 is enabled (step 407). If enabled, one command is provided to the compressor / restore 30 to restore the received compressed data (step 501 of FIG. 5).

In response to the command, compressor / restore 30 restores the compressed data (step 502). This restored data is then sent (step 503) to the control board 11B via the interface 19. The controller 14 of the control board 11B interprets (step 504) the commands included in the restored data to execute printing (step 505) according to the restored data.

Alternatively, in step 407, if compressor / restorer 30 of interface card 12 is not enabled, controller 17 is compressed to control board 11B via interface 19. The compressed data is transmitted (step 601 of FIG. 6). The controller 14 of the control board 11B confirms whether its own compressor / restor 40 is enabled and then sends a command (step 602) to restore the received compressed data. According to this command, the compressor / restor 40 restores the compressed data (step 603). The controller 14 then interprets (step 604) the instructions contained in the restored data and executes printing in accordance with this restored printing data 605.

As mentioned above, compressing and restoring data in an optimal manner is always achieved by comparing the performance of both compressors / restorers, and then performing data compression and reconstruction using a compressor / restorer with better performance. do. The choice of higher performance compression and decompression functions is made even if the performance of the interface card 12 changes due to the replacement of the unit.

If the transfer rate between the recording card's interface card and the control board is relatively low, it is preferable to transfer a smaller amount of data therebetween.

Therefore, in processing the compressed data from the host computer, even if the compressor / restorer 40 of the control board 11 has somewhat inferior performance than the compressor / restorer 30 of the interface card 12, the recording is performed. There may be a situation where better performance of the device is achieved by transferring compressed data with a smaller amount of data between the recording card's interface card and the control board.

Therefore, it is desirable to determine what compressor / restorer can be used by calculating the transfer rate between the interface card and the control board.

In addition, as shown in FIG. 3, each of the compressors / restors 30 and 40 of the interface card 12 and the control board 11 is supported by the compressors / restors 21 of the host computer 20. Supports algorithms having a higher compression ratio (eg, Huffman coding) than the compression rate (eg, travel length coding) of the compression / restore algorithm, and the interface card 12 before transferring data to the control board 11. It may be desirable to compress the data within. That is, the data compressed by the travel length coding and received by the host computer 20 is first restored in the interface card 12, and then compressed by Huffman coding and transmitted to the control board 12. FIG. As a result, it is restored by the compressor / restor 40 of the control board 11. This is effective when the transfer rate between the interface card 12 and the control board 11 is low.

The method of the invention described in the above-described flow chart can be embedded in a computer software program that can be executed by one or more controllers 22, 17 and 14. This software program can reside in memories 23, 31 and 15, can be standalone, can be written to media such as diskettes, floppy disks, can be inserted into carriers, loaded, and May be executed by the host computer 20 or the recording medium 10 in a manner.

Although embodiments of the present invention have been described with reference to the drawings, the present invention should not be limited to the manners mentioned in the above-described embodiments, and those skilled in the art, together with the prior art, will be described in the claims and detailed description of the present invention. Modifications or changes may be made without departing from the spirit of the invention on the basis of the statement. For example, in the above-described embodiments, each of the memories 15 and 31 stores each of the compression / restore capability information, but both performance information may be stored in the memories 15 and 31.

As described above, the present invention allows the compression / restoration function provided in the recording apparatus to be easily replaced so that the compression / restoration function provided in the host computer is compatible. This provides a recording device that can easily operate with a host computer having various compression / restore functions.

Further, in the present invention, the data compressor / restor installed on the control board of the recording apparatus is compared in terms of the performance of the compressor / restor of the interface card. This reduces the length of time required for data processing by performing restoration or compression of the data using any of the better compressors / restors for the restoration or compression of the data. In particular, the present invention is advantageous when the interface card is replaced and the performance of the compressor / restor installed therein varies.

While the invention has been described in conjunction with several specific embodiments, many alternatives, modifications, and variations will become apparent to those skilled in the art from the foregoing description. Accordingly, the invention described herein is intended to cover many alternatives, modifications, applications and variations within the spirit and scope of the appended claims.

Claims (14)

A recording apparatus connected to a host computer which compresses data to be recorded by a recording apparatus and transmits the compressed data to the recording apparatus. A control board having a first controller for controlling the recording device; An interface card detachably connected to said control board; The host computer communicates with the first controller via the interface card; The interface card, A first decompressor for restoring the compressed data received from the host computer; Comparing a data processing capability of restoring the compressed data of the control board with a data processing capability of restoring the compressed data of the interface card, and a second controller for controlling the first decompressor to restore the compressed data. A recording device comprising. 2. The apparatus of claim 1, wherein the control board comprises a second restorer board; The second controller compares the data processing capability of restoring the compressed data of the control board with the data processing capability of restoring the compressed data of the interface card, thereby recovering the compressed data. A recording device that enables one of the decompressors. 2. The recording apparatus of claim 1, wherein the first decompressor comprises a plurality of different algorithms for decompressing the compressed data. The recording apparatus of claim 1, wherein the interface card includes a first compressor for compressing data to be transmitted to at least one of the host computer and a control board. 5. The recording apparatus of claim 4, wherein the control board includes a second compressor for compressing data to be transmitted to at least one of the host computer and an interface card. 6. The method of claim 5, wherein the second controller compares the data processing capability of compressing the data of the control board with the data processing capability of compressing the data of the interface card, and then the first and the second controllers to compress the data. A recording device that enables one of the two compressors. An interface card in communication with a recording device and a host computer, the interface card detachably connected to a control board of a recording device having a first controller for controlling the recording device, A first decompressor for restoring the compressed data received from the host computer; Comparing a data processing capability of restoring the compressed data of the control board with a data processing capability of restoring the compressed data of the interface card, and a second controller for controlling the first decompressor to restore the compressed data. Including interface card. 8. The method of claim 7, wherein the second controller compares the data processing capability of restoring the compressed data of the control board with the data processing capability of restoring the compressed data of the interface card to recover the compressed data. An interface card enabling one of the first and second decompressors on the control board. 8. The interface card of claim 7, wherein said first decompressor comprises a plurality of different algorithms for restoring said compressed data. 8. The interface card of claim 7, comprising a first compressor for compressing data to be transmitted to at least one of the host computer and the control board. 11. The method of claim 10, wherein the second controller compares the data processing capability of compressing the data of the control board with the data processing capability of compressing the data of the interface card so as to compress the data. An interface card that enables one of the first compressor and the second compressor. 8. The interface card of claim 7, wherein said first compressor comprises a plurality of different algorithms for compressing said data. A recording data transfer method for transferring recording data from a host computer to a recording device, An interface card having a first restorer is detachably connected to a control board installed in the recording apparatus, the host computer communicates with the control board via the interface card, (a) a determining step of determining an algorithm for compressing and restoring recording data supported by the host computer and at least one of the card and the control board; (b) enabling the first decompressor if the control board does not have a decompressor capable of restoring compressed data according to the algorithm determined in step (a); (c) when the control board has one second recoverer capable of restoring the compressed data, data processing capability of restoring the compressed data of the control board and data restoring the compressed data of the interface card; A comparison step of comparing the processing performance; (d) enabling, according to the result of step (c), one of the first and second recoverers; (e) a transmission step of compressing the recording data in the host computer according to the algorithm determined in step (a), and transmitting the compressed data to the interface card; (f) a transmission step of recovering the compressed data in the interface card when the first recoverer is enabled, and transmitting the restored data to the control board; and (g) restoring the compressed data to the control board when the first decompressor is disabled to restore the compressed data within the control board. A computer readable medium incorporating an instruction program for execution by a machine for executing a method of transferring recording data from a host computer to a recording device, An interface card having a first restorer is detachably connected to a control board installed in the recording apparatus, the host computer communicates with the control board via the interface card, The method is: (a) a determining step of determining an algorithm for compressing and restoring recording data supported by the host computer and at least one of the card and the control board; (b) enabling the first decompressor if the control board does not have a decompressor capable of restoring compressed data according to the algorithm determined in step (a); (c) when the control board has one second recoverer capable of restoring the compressed data, data processing capability of restoring the compressed data of the control board and data restoring the compressed data of the interface card; A comparison step of comparing the processing performance; (d) enabling, according to the result of step (c), one of the first and second recoverers; (e) a transmission step of compressing the recording data in the host computer according to the algorithm determined in step (a), and transmitting the compressed data to the interface card; (f) a transmission step of recovering the compressed data in the interface card when the first recoverer is enabled, and transmitting the restored data to the control board; and (g) restoring the compressed data to the control board when the first decompressor is disabled to restore the compressed data within the control board.